3D Printing Anyone have experience with Amazon PETG?

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What are holes for?
 

mpitfield

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Hi, I just used PETGfor the first time and have only used filament from Prusa. It has been great to print with so far. sometimes the infill gets a bit stringy and the ends curl back is the only thing I have seen as an issue. I have read slowing the infill speed or trying the gyroid pattern may help. I printed this 5 fin rocket lower with internal venting for a 38MM casing this weekend. turned out GREAT!!. I was looking at the Amazon PETG but after reading this I just ordered more from Prusa.





View attachment 373041 View attachment 373042
Very cool concept of the cooling intakes. I am curious as to its affect on the performance and cooling.
 

Ryan Gillette

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Just had someone mention the casing getting hot and sticking to the plastic. So I went a bit crazy with the design and added cooling in the fins for fun. Planning on launching with some high power 38mm and see how it does. Should be fun. Just need the temperature to warm up a bit. -20 is a bit to cold for me to mess with rockets. Maybe I'll get lucky and it will whistle or something cool.
 

curtisheisey

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> Just had someone mention the casing getting hot and sticking to the plastic. So I went a bit crazy with the design and added cooling in the fins for fun. Planning on launching with some high power 38mm and see how it does.

In the 3d printed fin cans that I made, I used a standard motor mount tube as an insulator between the motor and the plastic. I will be interested in seeing your results.
 

jnobels

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I’m using Amaz3d PETG from amazon and it works really well. 0.05mm +z offset and really really slow speed (like 10mm/s) on the first layer - temps 245/70... Blue tape on the bed. my stock Prusia seems ok with this - but 245 is pushing the absolute max... The roll keeps tangling though which has spoiled a couple of prints on me.

It took a long time to get the temps and speeds dialled in. Couldn’t get the first layer to bond. Different PETG plastics behave very differently (some are ok at 220, others need upwards of 250). Going slow on the first layer and offsetting it very slightly, and finding the specific temps to use with the specific brand of filament is key.

Stringing seems unavoidable but for functional parts, not an issue. For cosmetic parts, PLA is probably a better choice.
 

jnobels

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PSA: Don’t print motor tubes. The printed tubes will warp with the heat and one day, you’ll find the motors just don’t fit anymore and your fin can is no longer flyable.

Tubes are cheap. Just use cardboard.
 

Mendal

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PSA: Don’t print motor tubes. The printed tubes will warp with the heat and one day, you’ll find the motors just don’t fit anymore and your fin can is no longer flyable.

Tubes are cheap. Just use cardboard.
Agree, speaking from experience.
 
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